What the heck happened in San Diego county between 2004 and 2008?

[Cyrusman]

Can someone please tell me what happened to San Diego county between 2004 and 2008? This is my home county and while I grew up in the more rural conservative parts I don’t understand why the GOP lost so much ground here during that time. I could see the 2008 results now, but why did Republicans win this county in 2004 by 6 points and then lose it by 10 in 2008? That’s a big swing for a very populated county that you don’t see often. Also McCain comes across as a decent fit for the CA GOP he wasn’t Trump. With the military presence and this county always being more conservative compared to many areas of California I don’t get it. Also the GOP has never recovered since then in this county.

[TDAS04]

Actually, the swing in the county wasn’t much larger than that of the entire state, and San Diego didn’t swing as much as next-door Orange County.  For virtually all of Southern California—and the Southwest outside McCain’s home state of Arizona—trends were leftward. Obama handily outperformed Kerry among Hispanics, Asians, and suburban whites—the area’s main demographics.